Project Summary/Abstract The HIV epidemic continues to present a significant global burden. Although they represent half of the global epidemic, development of effective prevention strategies for women has been slow. Tenofovir-based pre-exposure prophylaxis has demonstrated success in reducing HIV infections however two failed clinical trials have raised concern about effectiveness in women. Host factors such as inflammation, hormones, and the vaginal microbiome may modulate not only HIV risk, but drug efficacy as well. In this career development award, advanced training will be obtained in the techniques and approaches required to develop an independent scientist proficient in performing the translational studies required to better elucidate the complex mucosal environment of the female genital tract. This research proposal will lay the ground work studies characterizing the effect of hormones, inflammation, and the vaginal microbiome on drug exposure and efficacy in cervical tissues. Active metabolites of tenofovir and other nucleotide analogues will be measured in cervical biopsies from HIV positive women from U.S. and Ugandan cohorts receiving hormonal contraception. Quantification of pro-inflammatory cytokines and 16S DNA sequencing will be performed in swabs to assess inflammation and the vaginal microbiome of these women. Ex vivo tissue models will be used to determine associations between inflammation, nucleotide analogue activation, and viral inhibition. Completion of these research aims, with the guidance of an interdisciplinary mentoring team, will be supplemented by advanced coursework and workshops in statistics, immunology, microbiomics, and research ethics. This research and training plan are designed to result in the preliminary data and developed expertise necessary to prepare for an R01 submission elucidating the complex interplay between hormones, microbiome, inflammation, drug disposition, target cell expression, and drug potency in the female genital tract.